A dad writes: "For the first 12 weeks after you were born, I didn't like you very much."

Postnatal depression isn’t something that’s usually associated with men, and yet on average, one in 10 new dads struggle with it.

In a heartbreakingly honest blog post, one dad has spoken about his own personal battle with the debilitating mental illness.

Penning an open letter to his 11-month-old daughter, Isabelle, Welsh dad Ross Hunt admitted there were times when he “hated” his baby.

“This might not sound very nice. But for the first 12 or so weeks after you were born, I didn’t like you very much,” he wrote on his blog, Isablog.

“There were times when I hated you. I regretted having you, and thought that my life had been ruined by you being born. I know that’s hard to read, but trust me, it’s incredibly hard to write too.”

He went on to write that while things have gotten easier, he still experiences bad days.

Ross told Isabelle these feelings were never actually his, rather they had been brought on by his depression, something he'd been struggling with since before she was even born.

"It’s been there a long time, and is probably always going to be there in some form. But I never thought it would try to tell me that I didn’t like you," he wrote.

"You see, depression can cause a person to think horrible things without their control, and make a person feel unhappy, angry, or even worse, make a person feel nothing at all. And that’s what it often did to me."

Ross said his depression often made him feel like running away shortly after his daughter was born, but he's happy he ignored his feelings and stuck around.

As shocking as his admission is, it's something an increasing amount of other dads struggle with, too.

In an article published on Mamamia! last year, a Perth dad, Jonathan Miles, said he lost the will to live six weeks after his son, Callum was born.

"I actually said to my wife that she’d be better off without me, that I was holding her and our boy back," he said.

"It’s probably the closest I’ve been to suicide."

Jonathan says he only started to recover after realising he needed help, and taking the right actions to get that help, whether it was upping his dosage of antidepressants or asking his parents to assist with the baby occasionally.

And asking for help is the key to recovery.

LISTEN: According to Australia's Medical Association, other mothers cause postnatal depression. Post continues below.

According to research in Sweden last year, less than one in five fathers suffering from depression actually sought help, as reported by The Guardian.

And while many new mums are usually assessed for signs of postnatal depression, new dads aren't offered the same screening processes.

It's worrying, given postnatal depression in men is on the rise, with 28 percent of all new dads in the Swedish study showing varying levels of postnatal depression.

If you or someone you know is experiencing depression, you can find help by following these links and contacting beyondblue or Lifeline.